Stephan, why did you prohibit building mana.c without ROOT and HBOOK
support? I think such a configuration is valid and should be allowed.
Also, this prohibition broke the Midas Makefile, it now bombs building
mana.c. The Makefile is setup for building hmana.c with HBOOK support,
rmana.c with ROOT support (if ROOTSYS is set) and mana.c without HBOOK and
ROOT support (currently bombs on #error in mana.c).